from the not-yet-a-tri-corder dept.Gina Miller writes "The Chicago Sun Times Nanotech leading to diagnoses by handheld reports that Northwestern University's Institute for Nanotechnology in collaboration with Nanosphere Inc. are in the midst of developing a hand held device based on nanoparticles, that could give instant diagnosis via bodily fluids. The device is based on nanoparticles that exibit color which along with genetic markers of DNA could together turn diagnosis into color coding detection. The chip that will go on the inside of the handheld, is being developed by Nanosphere Inc. The article also discusses another company, NanoInk and how their work with dip-pen nanolithography could pertain to the color coding aspect by allowing the chip to sample specific sequences in the DNA that the gold particles have color-coded."

2 Responses to “Nanotech leading to diagnoses by handheld”

Having spent a large chunk of yesterday in a waiting room, I'm eager for a full-blown medical tricorder.

Human blood contains gobs of diagnostic data, but our current blood tests use it rather inefficiently. Because of costs and insurance liability, we collect separate blood samples for every test. When this kind of technology really hits its stride, we'll be able to perform dozens or hundreds of tests on a drop (or a few drops) of blood, and we'll be able to lance an arm or finger instead of taking it from a vein.

Unfortunately the relevant Nanosphere web page isn't much more informative than the article Gina found in the Chicago Sun Times. The nanoparticles change color, but how and in response to what, and why they're particles and not tendrils or patches on a surface, there's no indication.

The abstract of the most recent patent reads: The invention provides methods of detecting a nucleic acid. The methods comprise contacting the nucleic acid with one or more types of particles having oligonucleotides attached thereto. In one embodiment of the method, the oligonucleotides are attached to nanoparticles and have sequences complementary to portions of the sequence of the nucleic acid. A detectable change (preferably a color change) is brought about as a result of the hybridization of the oligonucleotides on the nanoparticles to the nucleic acid. The invention also provides compositions and kits comprising particles. The invention further provides nanomaterials and nanostructures comprising nanoparticles and methods of nanofabrication utilizing the nanoparticles. Finally, the invention provides a method of separating a selected nucleic acid from other nucleic acids.

My interpretation is that the nanoparticle has little widgets on it which bind to short DNA sequences, and visibly change color when they have thus bound. I don't know how many binding events are required before the color change is perceptible to the naked eye. Later in the same patent we find the scope of applicability:

I would want to see this gadget perform hundreds of tests in parallel, ideally with a very small quantity of blood. A drop or two can be obtained by lancing the finger or arm, rather than sticking a needle in a vein to collect a vial. In the current diagnostic paradigm, we collect a vial from a vein and do a small number of tests on it. The technology up to now has restricted us to this approach, but this method would open up the possibility for highly parallel testing.

Parallel testing is good for doctors and patients, but maybe bad for pharmaceutical companies, who would no longer be able to sell hundreds of different testing kits. To get the same revenues from the market, they might need to charge exhorbitant prices for each parallel test. New companies trying to sell the parallel tests at more reasonable prices might be blocked by regulatory legislation – there could be very large sums of money involved. The obviously desirable long-term outcome would be to end the cycle of medical poverty that makes us vassals of our HMOs.

As I get older, I like technology better and better, but I fear economics more and more.